Receivables - Receivables (Detail) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Receivables [Abstract]
Reinsurance (Note 16)	$ 4,204	$ 4,455
Insurance	2,481	2,365
Receivable from brokers	124	296
Accrued investment income	395	394
Federal income taxes	14	52
Other, primarily customer accounts	520	477
Total	7,738	8,039
Less: allowance for doubtful accounts on reinsurance receivables	25	29
allowance for other doubtful accounts	38	50
Receivables	$ 7,675	$ 7,960

Amount, before allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business.

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Interest, dividends, rents, ancillary and other revenues earned but not yet received by the entity on its investments.

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Amount of allowance for credit loss on accounts receivable.

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Carrying amount as of the balance sheet date of income taxes previously overpaid to tax authorities (such as U.S. Federal, state and local tax authorities) representing refunds of overpayments or recoveries based on agreed-upon resolutions of disputes. Also called income tax refund receivable.

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Amount due from parties in nontrade transactions, classified as other.

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Carrying amount as of the balance sheet date, net of allowance for doubtful accounts, of all premiums and other types of receivables due from other persons or entities.

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Gross amount, as of the balance sheet date, due the entity from (a) agents and insureds, (b) uncollected premiums and (c) others, before deducting the allowance for doubtful accounts.

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Amount receivable from broker-dealers and clearing organizations, including, but not limited to, securities failed-to-deliver, certain deposits for securities borrowed, open transactions, good faith and margin deposits, commissions and floor brokerage receivables.

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Amount of allowance for credit loss on reinsurance recoverable.

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Amount before valuation allowance recoverable under reinsurance contracts. Examples include, but are not limited to, settled and unsettled claims, incurred but not reported losses, loss adjustment expense, premium paid, policy benefits and policy reserves.

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